    [From the U.S. Government Printing Office, www.gpo.gov]

                  HURRICANE EVACUATION

                               PLAN

               Phase One- An Analysis of Evacuation
           Capability and Vulnerability to Hurricanes in
                       New Hanover County

                               JUNE 1984
                   Prepared by the New Hanover County Planning Department

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                                                  INFORMATION CENTER

                                   U.S. DEPARTMENT OF COMMERCE NWAP
                                   COASTAL SERVICES CENTER
                                   2234 SOUTH HOBSON AVENUE
                                   CHARLESTON, SC 29405-2413

                                   HURRICANE EVACUATION PLAN

                     Phase One - An analysis of evacuation capability and
                       vulnerability to hurricanes in New Hanover County

                                          JUNE, 1984

                    Prepared by the New Hanover County Planning Department

                                                    property of CSC Library

                                               The preparation of this document was
                                               financed, in part, through a Coastal
                                               Area Management Act grant provided by
                                               the North Carolina Coastal Management
                                               Program, through funds provided by the
                                               Coastal Zone Management Act of 1972, as
                                               amended, which is administered by the
                                               Office of Coastal Zone Management,
                                               National Oceanic and Atmospheric
                                               Administration

    - -Figure on cover from Simpson, R., and H. Riehl, 1981, The Hurricane and It's
       Impact, Baton Rouge, LA, Louisiana State University Press.

                                 TABLE OF CONTENTS

                                                                   Page No.

    I.      PURPOSE AND SCOPE I

    II.*    THE HURRICANE THREAT                                              1
           A.  Background I
           B.  Potential Hurricane Impacts                                   2
           C.  Hurricanes and New Hanover County                             6

    III.    THE SEVERITY OF EXPOSURE OF NEW HANOVER COUNTY TO HURRICANES    6

    IV.     ANALYSIS OF EVACUATION                                           13
           A.  Components of Hurricane Evacuation Time                      13
           B.  Evacuation Times for New Hanover County                      14

    V.      ANALYSIS OF EVACUATION SHELTERS                                  19

    VI.     CONCLUSIONS AND RECOMMENDATIONS                                  19

    V.      REFERENCES                                                       20

                                HURRICANE EVAUATION PLAN

    I.    PURPOSE AND SCOPE

         This Hurricane Evacuation Plan analyzes the capability of expected
    evacuation routes and shelters to safely accomnmodate the evacuation of County
    residents from hurricane-vulnerable areas. This Plan represents the major
    product of the first year of a two-year comprehensive, Countywide planning effort
    that will result in an overall "Hurricane Hazard Mitigation and Post Disaster
    Plan". This plan is being funded by a grant fram the North Carolina Office of
    Coastal Management under authority of the Coastal Area Management Act (CAMA).

         The products of this two-year planning study will be:

         1. Hurricane Evacuation Plan (year one)
             a. hazard area map
             b. analysis of expected evacuation routes
             c. assessment of existing evacuation routes and sites
             d. proposed mitigation policies if sites and routes are assessed
                 to be inadequate
             e. up-dating of the operational elements of the existing
                 "Hurricane Evacuation Plan", prepared by the New Hanover
                 County Civil Preparedness Agency.

        2. Preparation, printing and distribution of evacuation instructions
            and hurricane season warning poster (year one)

        3. Storm Hazard Mitigating Plan (year two)
            a. Inventory and analysis of existing land uses and structures
                in the hazard areas
            b. Economic risk assessment
            c. Hazard mitigation policies based on 3a and 3c.

        4. Post Disaster Reconstruction Plan (year two)
            a. Guidelines for post disaster reconstruction including the
                phasing of damage assessment, temporary moratorium, and post
                disaster developmnent standards
            b. Establishment of damage assessment teams and standards.

    II.* THE HURRICANE THREAT

        A. BACKGROUND

        A hurricane resembles a large, shallow funnel with air flowing in a counter
    clockwise direction from high pressure areas along the storm's periphery to a
    concentrated center of extremely low pressure. Winds may reach 200 miles per
    hour near the center of the hurricane, even though the center, or the "eye", is
    an area of relative calm.

                                        Page I

        Atlantic hurricanes generally begin as low intensity storm systems in the
    Ca'rribean Sea or the Western Atlantic Ocean. Hurricanes form by passing through
    increasingly intense phases:

        -tropical depression (winds less than 40 miles per hour)
         -tropical storm (winds between 40 and 73 miles per hour)
         -hurricane (winds greater than 73 miles per hour)

        Although the hurricane season runs from June through November, 90% of all
    recorded hurricanes in North Carolina have occurred in August, September, and
    October. Hurricanes tend to follow a westward parabolic path and generally move
    forward at a speed of around 15 miles per hour. Both the direction and the
    forward spead of the hurricane path, however, can vary dramatically (McElyea et
    al, 1983).

         Presently, local governments in New Hanover County have the responsibility
    of ordering evacuation based on their judgement that a hurricane is threatening.
    The local governments generally use the Hurricane Watch and Warning system of the
    National Weather Service as signals for action. A Hurricane Watch is issued when
    a hurricane is near enough that everyone in the area should listen for subsequent
    advisories and be ready to take action. The National Weather Service issues a
    Hurricane Warning when hurricane conditions are considered to be highly likely.
    The goal of the Service is to issue the warning at least 12-18 hours before the
    hurricane eye reaches the area. The Hurricane Warning generally is the signal
    used by local governments to order evacuation.

         Attempting to predict the path and travel time of a hurricane is coimplicated
    by the tendency of the hurricane to vacillate significantly along its path, by
    the large approximately 125 mile diameter of a hurricane, and by a lack of
    recorded data on previous hurricanes. The National Weather Service has recently
    developed a probability system in hurricane forecasting. This system gives the
    probability increments, in percentages, of a hurricane eye gaining landfall
    within 65 miles of a given comnunity for five time periods: (1) through 24
    hours, (2) 24-36 hours, (3) 36-48 hours, (4) 48-72 hours, and the total
    probability through 72 hours. These probabilities, however, are not related to
    the intensity of the storm. This new probability system presently operates in
    addition to and independent of the Hurricane Watch and Warning System (Carter,
    1983).

         B. POT'ENTIAL HURRICANE IMPACTS

         Since the turn of the century, casualties from hurricanes have generally
    decreased due to improvements in monitoring and warning systems and local
    preparedness and evacuation planning. The potential for substantial loss of life
    remains, however, as coastal population increases and the tourism traffic grows.
    Property damage, in contrast to casualties, has increased exponentially. These
    trends are shown in Figure 1.

         Hurricanes are typically classified according to the Saffir/Simpson Damage
    Potential Scale. Hurricanes are designated on a scale of I to 5 (described in
    Table 1) based on the hurricanes present wind speed, storm surge level, and
    atmosphere pressure.

                                         Page 2

       *Additional hurricane factors causing casualties and damage include wave
    action and erosion.

         (1) Wind damage
             Wind strengths will increase as the hurricane center approaches
             land. Peak gusts may exceed 200 miles per hour. Friction from the
              land surface will generally dissipate high winds although a narrowing
             zone of wind damage, 30-35 percent of that at the shoreline, can
             extend much further inland. In addition, tornadoes may occur with
             the hurricane. Hurricane Agnes, for example, spawned 15 tornadoes
              in Florida, resulting in 4.5 million dollars of damage (McElyea et al
              1983).

         (2) Flooding Damage
             Approximately 90% of hurricane deaths and the majority of property
             damages result f ran flooding caused by hurricane storm surges and
             precipitation. The storm surge results from the hurricane winds
             and low pressure system pushing up an enormous swell of water
             before it. The height of the surge depends on wind speed, normal
             water depth, storm trajectory, forward speed of the storm,
             and tide conditions. Hurricane Hazel in 1954 created a surge of
              14.7 feet above mean sea level at Holden Beach. The increase in
              flood elevation may be 50% greater behind the barrier islands due to
              funneling of the water in shallow and narrow estuaries and bays.
              Flooding damage is worsened by the lifting up and use of debris,
             boats, and structures as battering rams. Saltwater contamination
              of land may result. Precipitation, adding to the flooding problems,
             may equal 10" or more in a 24 hour period (McElyea et al 1983)

         (3) Wave Action
             The impacts of the storm surge are increased greatly by the effects
              of waves. First, waves on top of a surge can reach and flood areas not
              reached by the surge itself. Second, waves act as direct battering
              rams, their force depending upn the velocity and size of waves. The
             waves are likely to be greatest along the ocean shoreline where winds
              are greatest and where the ocean bottom falls of f rapidly. Generally,
              the waves height will be equal to 50% of the depth of the storm surge
              (McElyea, et al 1983).

         (4) Erosion
             High winds, storm surge, and waves may cause significant erosion,
              especially on barrier islands. Vast amounts of sand may be removed
              from the beach front. Dunes may be breached by washover from waves.
              Finally, inlets tend to form or widen in response to storm surge
              build-up behind the barrier island. In 1967, Hurricane Beula cut 31
              inlets through Padre Island, Texas. Although many of the inlets may
              eventually fill back in, the damage to structures and transportation
              networks will already have occurred.

                                        Page 3

                             Figure 1
    Figure 2.3: Deaths and Damages from Hurricanes in the United States

          2200                                                        5500

          2000 -    DAMAGE                       DEATs              -5000
               (Adjusted to 1957-59 base)

          isO0-                      m                              - 4500

       MA                                                                21,M
          1600 -                                                    -34000
                       >~~~~~~~~~~~~~~~
       C

       1 1400-          -.o300
              -J                                                           m

       a                      -I,                                         I-
       4n 1000 -                                                    -23500

                                                    P~~~~~~~~~MI
         6 100 -                                                    -30

                       8~~~~~~~~~~~~~~
          100 -                                                     -2500 MI
                 Z~~~~~~~ z

          800-
                      I-Z-E-f          HEMN-               -2000w

                          Iource:(jc;jaeta00                            1983

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                     2Q0-~~~~~~~~~~~�                     fl~~~~~~:  - 1500

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     Table   1: Saff ir/Simpson Damage Potential Scale

    Se   No. 1-Winds of 74 to 95 miles per hor. Damage primrily to shrubbery.
    trees. foilage. and unanchored mobile homes. No real damage to other structures.
    Some damage to poorly constructed signs. Andl/or: storm surge 4 to 5 feet above
    normal. Low-lying coastal roads inundated, minor pier damage, some small craft
    in exposed anchorage torn from moorings.
    Sale No. 2-Winds of 96 to 110 miles per hour. Considerable damage to shrub-
    bery and tree foliage; some trees blown down. Major damage to exposed mobile
    homes. Extensive damage to poorly constructed signs. Some damage to roofing
    materials of buildings: some window and door damate. No major damage to
    buildings. And/or: storm surge 6 to 8 feet above normal. Coautal roads and low-
    lying eicape routes inland cut by rising water 2 to 4 hours before arrival of
    hurncane center. Considerable damage to piers. Marinas flooded. Small craft in
    unprotected anchorages torn from moorings. Evacuation of sose shoreline resi-
    dences and low-lying isiland areas required.
    Seale No. 3-winds of II111I to 130 miles per hour. Foliags torn from trees:
    trees blown down. Practically all poorly constructed signs blown down. Some
    damage to roofing matmlerals of buildings; some window and door damage. Some
    structural damage to small buildings. Mobile homes destroyed. And/or: storm
    surge 9 to 12 feet above normal. Seriour Iooding at coast and many smaller
    structures near coast destroyed; larger strucmtu  near eoot damaged by battering
    waves and floating debris. Low-lying escp routes inland cut by risil water 3
    to 5 hours before hurricane center arrives. Flat terrain  . feet or les above mn
    vel flooded inland 8 miles or mom. Evacuation of low4ying residences within
    several blocks of shoreline possibly required.
    Selb No. 4-Winds of 131 to 155 miles per hour. Shrmbr and trea blown down:
    all signs down. Extensive damage to roofing materials. window  and door. Corn-
    pklete failure of roofs on many small residences Complete detruction "f mobile
    homes. And/or: storm surge 13 to 18 feet above normaL Flat terrain'10 feet or
    less above sea level flooded inland as far as 6 miles. Major damage to lower
    Mloors of structures near shore due to flooding and battering by waves and floating
    debriLr Low-lying escape routes inland cut by rising water 3 to S hours before
    hurricane center arrive. Maor erosion of beaches. Mussive  vacuaon  of all
    residences within 500 yards of shore pomrbly required, and of single-story resi-
    dences on low ground within 2 miles of shore.
    Sale No. =-Winds grater than 155 miles per hour. Shrubs and tree blow
    down: considerable damage to roofs of buildings; all siln  dow. Very severe
    and extensive damage Io windows and doors. Complete failhre of roofs o  many
    residence  and industrial buildip. Extensive shattering of  OM  in windon Md
    doors. Some complete building failures. Small buildings orturnd  or blwn
    away. Compkte destruction of mobile bomes. And/on stom sure lpter than
    18 feet above normal. Major damage to lower  oo  of all strces  kW  than
    15 feet above sea level within 500 yards of sho. Low-lying escape routes inlaud
    cut by rising water 3 to 5 baom before hurricane censr arrive. Massive evacua-
    tion of residential areas on low ground within I to 10 miles of shore possbly
    required.

     Source: (McElyea et al, 1983)

                              Page 5

        C. HURRICANES AND NEW HANOVER COUNTY

         Since 1899, North Carolina has received direct hits from 21 hurricanes,
    eight of them classified as 'major" (3, 4, or 5 on the Saffir/Siinpson Scale).
    Numerous other hurricanes have also impacted North Carolina, including lesser
    hurricanes and hurricanes staying out at sea or bitting South Carolina. As
    indicated in Figure 2, New Hanover County has approximately a 6% chance of being
    directly struck by a hurricane any given year. As indicated in Table 2, a number
    of hurricanes have either directly or indirectly impacted New Hanover County
    beaches in the 20th Century (USCOE, 1983). It should be noted that certain
    impacts such as erosion along beaches may be caused by indirect impacts of
    hurricanes or of lesser storms, such as "northeasters."

         An account of Hurricane Hazel when it struck North Carolina on October 15,
    1954, illustrates the impacts caused by a hurricane. The storm surge exceeded 14
    feet and wind velocities were estimated at 140 miles per hour. Every fishing
    pier in North Carolina was destroyed. All buildings were destroyed at Holden
    Beach and Ocean Isle. At Long Beach, 352 of 357 homes were lost. At Carolina
    Beach, 475 buildings were destroyed and 1,365 were damaged. Over 1,000,000 cubic
    yards of sand were deposited on Carolina Beach roads. Wrightsville Beach was
    submterged under five feet of water and 89 homes were lost. A total of 191 people
    were killed in the State and $125,309,000 of damage were caused (McElyea, 1983).

    III.* THE SEVERITY OF EXPOSURE OF NEW HANOVER COUNTY TO0 HURRICANES

          All of New Hanover County is vulnerable to hurricane forces to a varying
    degree, as evidenced by Table 3. The entire County will be subject to possible
    wind damage. However, certain areas will be highly exposed to shoreline erosion
    and scouring, wave action and battering, and flooding, in addition to direct wind
    damage. These areas, which have a severity rank of one, are Ocean Erodible Areas
    of Environmental Concern (AECs), Inlet Hazard AECs, and Estuarine Shoreline AECs.
    These areas are the most critical areas for hurricane protection planning with
    regard to exposure to hurricane forces.

          Ocean Erodible AECs start at mean low water and go landward a distance from
    the vegetation line equal to 30 times the long term annual erosion rate plus the
    shoreline recession projected for a 100 year storm. This width generally varies
    between 200-400 feet. Inlet Hazard AECs are based on statistical analysis of
    inlet migration (using a 99.9% confidence interval for a 10 year period) and such
    factors as man-made alterations or unusual hydrologic features. The width of
    this area may vary from as little as 250 feet for stable inlets to 4,000 feet in
    more dynamic areas. This hazard area applies only to existing inlets, not to
    past or potential inlets (Owens, 1981). Detailed maps prepared by the U. S.
    Corps of Engineers and the N. C. Office of Coastal Management at a scale of I"-
    400' are available for review at the County Planning Department.

                                        Page 6

    Figure 2    Percentage Probability that a Hurricane
                (winds exceeding 73 mph) or a Great Hurricane
                (winds exceeding 125 mph) Will Strike a
                50-Mile Segment of the U. S. Coastline
                in Any Given Year.

                                               47

                                        f~~~~~~~~~~~~~i

                                     30.

                    SoreI'mle   t  l   93

                              Page~~ 71

                                     Table 2
                              >. HISTORICAL RECORDS-
                                        HISTORICAL RECORDS  Source: (USCOE, 1982)

    1.  Lists of Hurricanes.  The following tables present a chronological list
    of tropical hurricanes which have likely affected the Wrightsville Beach
    area.  However, many of them caused no appreciable damage and others prior
    to 1871, which caused some damage, may not be listed:

                    Records of 18th and 19th Century Hurricanes
                     Affecting the North Carolina Coastal Area

           Date                                                    DOate
    Year, Month, and Day                                -   Year, Month, and Day

        18th Century                                         19th Century (cont'd)

    1700 September   16                                      1844 September   14
    1713 September   16                                      1846 August       16
    1728 August      -                                       1853 September   7
    1728 September   14                                      1854 September   8
    1752 September   15                                      1857 September   12
    1753 September   15                                      1861 October      -
    1757 October     -                                       1871 August       18-19
    1758 August       23                                     1871 November    14
    1761 June         1                                      1873 September   22-24
    1761 September   23                                      1873 October      6-8
    1770 June        6                                       1873 November    17
    178L August       10                                     1874 September   28
    1783  -          -                                       1874 November    22
    1785 September   22-24                                   1875 October      13
    1797 September   -                                       1876 September   17
                                                            1877 November    2
        19th Century                                         1878 September   12
                                                            1878 October      22
    1804 September   7                                       1879 August       19
    1811 September   10                                      1880 August       15
    1913 August      27                                      1881 August       27
    1814 July         1                                      1881 September   9
    1815 September   28                                      1883 September   11
    1821 September   2                                       1885 August       24-25
    1822 August      -                                       1888 October      11
    1822 September   27                                      1893 August       28
    1827 July        30                                      1893 October      13
    1827 August      24-25                                   1894 September   27
    1830 August       16                                     1894 October      9
    1837 August       1                                      1896 September   20
    1837 August      20                                      1897 November    7
    1837 October     9                                       1898 October      2
    1838 November    26-28                                   1899/October      30
    1842 August      24

                                       Page 8

                                       Table 2 cont.
                     Records of 20th Century Hurricanes Affecting
                        New Hanover County, N.C., Beach Areas

       Year       Month and Day    Notes, Severity, Damage Areas, etc.

                                   Major and Moderate

    11904        September 14       Moderate, S.E.N.C.

    1904        November 13         Moderate, N.C. coast

    11906        September 17       Severe, S.E.N.C. Barometer at Wilm., 27.90

    1910        October 19          Moderate, Wilmington area - inland

    11913       September 2-3       Hatteras - major, N.E.N.C.

    1916        July 19-20          Moderate, N.E.N.C. Heavy rainfall

    1918        August 24           Hatteras, moderate, small, N.E.N.C.

    1924        August 25           Moderate, skirted N.C. at Hatteras

    11925       December 2          Moderate, N.E.N.C. Unusual storm
                                   Barometer 28.90 near Wilmington

    1930        September 12        Hatteras and vicinity - moderate.
                                   Barometer 29.71 at Wilmington.

    11933        September 16       Severe N. of New Bern to Va. Capes,
                                  moderate to minor elsewhere. Barometer at
                                  Hatteras, 28.25 inches.

    1934        July 21-25          Very minor in vicinity of Wilmington

    11944       August 1-2          Wilmington - severe, S.E.N.C.  Barometer
                                  at Wilmington, 29.41

    11944        September 14       Hatteras - severe.  Barometer at Hatteras,
             1'~~~ ~         ~ 27.97.

    1945        September 15-16   Beaufort area - moderate.

    1954        August 30           Moderate to light - whole coast - "Carol"
                                  Barometer 29.41 at Wilmington.

    11954       October 15         Very severe, S.E.N.C. "Hazel."  Barometer,
                                  27.70 at Little River, S.C.

    I Storms actually striking or entering N.C. coast with destructive force.

                                   Page 9

                                Table 2 cont.
                    Records of 20th Century Hurricanes .Affecting
                       New Hanover County, N.C., Beach areas

      Year       Month and Day    Notes, Severity, Damage Areas, etc.

                                  Major and Moderate -- Cont'd

    11955       August 11-12        Severe, E.N.C., heavy rains - "Connie."
                                   Barometer, 28.40 at Fort Macon, N.C.

    11955       August 17           Moderate in Wilmington Area - "Diane."
                                  Barometer, 29.13 at Wilmington, N.C.

    11955       September 19        Severe, E.N.C., excessive precipitation.
                                  Barometer, 28.35 at Morehead City, N.C.
                                  "Ione."

    11958       September 27        "HeLene."  Severe in Cape Fear area.
                                  Maximum 5-minute wind, 69 mph.  Minimum
                                  barometer 28.80 inches - both at Wilm., N.C.

    11960       September 11-12   "Donna."  Severe in Cape Fear area, worse in
                                  vicinity of Morehead City, N.C. Maximum 1-
                                  minute wind velocity'in Wilmington, 53 mph,
                                  NW; minimum barometer 28.41 inches.

                                  Minor

    1901        September 18

    1902        June 16

    1903        September 16        Very minor - delayed flight of Wright Brothers

    1908        August 31           Cape Lookout damaged - very unusual storm.

    1916        July 14             Heavy rain in interior.

    11920       September 20       Cape Fear River area - small storm - little
                                  damage.

    1923        October 23

    1924        September 16-17

    1924        September 30        Minor in Wilmington area.

    1928        September 18        S.E.N.C. Barometer, 29.12 at Wilmington, N.C.

                                 Page 10

                                        Table 2  cont.

                     Records of 20th Century Hurricanes Affecting
                        New Hanover County, N.C., Beach Areas

      Year       Month and Day    Notes, Severity, Damage Areas, etc.

                                   Minor -- Cont'd

     1929        September 1-2       Very minor

     1934        September 7-8       Barometer at Hatteras, 28.56

     1935        September 5-6

    1937        July 31             Minor, not a hurricane in N.C.

    1937        August 2-8          Minor, not a hurricane in N.C.

    1937        September 26-30   Minor, not a hurricane in N.C.

    1938        September 21        Hatteras and vicinity

    1938        October 23-24       Minor, not a hurricane in N.C.

    1940        August 15           Very minor, heavy rain

    1940        September I         Heavy rains

    1942        October 11-12       Very minor, not a hurricane in N.C.

    1944        October 20

    1945        June 24

    1945        November 5         Very minor

    1946        July 6              Very minor

    1946        September 19        Minor

    1947        October 12-13

    1950        August 19-20

    1951        October 4

    1952        August 30           Very minor "Able."

    1953        August 13           "Barbara" Cape Lookout area.

    1954        September 10        "Edna"

    1973        February 17         Erosion and some property damage

    1979        September 5         "David" I-year frequency storm

                                 Page 11

                                Table 3
                          Severity of Risk in Hazard Areas

                                    Exposure to Damaging Forces
      Hazard Area            Severity  Erosion/  Wave Action/  Flooding  High
                            Rank      Scour      Battering              Wind
    ocean Erodible AEC      I    1
    Inlet Hazard AEC I
    Estuarine Shoreline AEC  I  1                      .
    V-zone                       2         o
    Wetland AEC                  2          0           90                    0
    A-zone                       30
    Rest of Coummunity           4

        Exposure Level: High (.), Moderate (o), Low()
                                      Source: (McElyea et al, 1983)'

                                Page 12

        The Estuarine Shoreline-AEC's cover all land within 75 feet of the mean high
    water line. Estuarine lands may be subject to storm surge and general flooding.
    Federal Flood Insurance V zones, which tend to overlap the above AECs, represent
    those areas likely to be flooded by a 100 year storm and exposed to scouring
    /erosive wave action. Coastal Wetland AECs, located generally within the
    Estuarine Shoreline AEC, are low lying areas and would tend to be flooded.
    Federal Flood Insurance A Zones are likely to be inundated in a 100 year storm
    but would not be subject to scouring/erosive wave action. The extent of the
    Estuarine Shorelines and Coastal Wetlands are mapped on Figure 4. (attached as
    fold-out maps in the back of this report) A more detailed map at I" = 3000' is
    available for review at the County Planning Department. The extent of the V and
    A zones are mapped on Figure 5. (attached as fold-out maps in the back of this
    report) Maps at a scale of I" = 2000' prepared by Federal Emergency Management
    Agency (FEMA) of the V and A zones are available for review at the County
    Planning Department.

    IV ANALYSIS OF EVACUATION TIME

        A. COMPONENTS OF HURRICANE EVACUATION TIME

           Evacuation time is defined as
           11... the minimum amount of time before projected hurricane
           eye landfall that local decision makers must allow for
           safely completing the evacuation under the particular
           conditions of the approaching hurricane." (Stone, 1983, p. 7)

           Evacuation time is composed of two separate components, clearance time and
    pre-landfall hazards time.

          (1) Clearance Time

              Clearance time is defined as the time necessary for the relocation of
              all vulnerable evacuees to a safe area once the official evacuation
              order is issued. Clearance time is composed of three subcomponents:
              mobilization time, travel time, and queuing delay time.

            (a) Mobilization time is that period between the issuance of the
                 evacuation order and the departure'of the vehicles. It represents
                 time for evacuees to learn of the evacuation order, pack some
                 belongings and leave. Three hours/household for mobilization is a
                 typical time period used in other studies and corresponds with
                 preliminary survey results of residents and tourists during August
                 and September, 1983, on Wrightsville, Carolina and Kure Beaches.

                                         Page 13

            (b) Travel time is the period necessary for the vehicles to travel the
                 length of the evacuation route at an anticipated speed, assuming
                 no queuing delays

            (c) Queuing delay time is the amount of time spent by vehicles in
                 traffic jams when the capacity of the evacuation routes are
                 exceeded by the number of vehicles entering those routes. A
                 bottleneck would occur, for instance, where four lanes converge
                 onto a two lane bridge.

          The roadway capacity factors for the study, taken from the carrying
    capacity study for Currituck (Collins, 1983) are 1575 vehicles per hour (vph) for
    two lane roads and 3222 vph for a four lane road. These levels of capacity would
    increase for roads with shoulders or parking lanes. These factors take into
    account the following adjustments:

          - common roadway capacity standards for engineering purposes
          - 35% reduction in capacity due to adverse weather
          - 15% further reduction for stalled cars
          - 10% further reduction for emergency vehicle use

          It should be noted that traffic during evacuation should be strictly
    controlled, using policemen for directing traffic and generally requiring one way
    traffic.

          (2) Pre-Landfall Hazards Time

               This represents the period of time between when evacuation
               from the vulnerable area first becomes extremely difficult
               due to either gale force winds or storm surges that inundate
               evacuation routes, and when the eye of the hurricane reaches
               the coast. A typical value for a severe hurricane scoring a "5"
               on the Saffir/Sim~pson Scale is four hours. This amount of time
               plus clearance time equals evacuation time.

         B. EVACUATION TIME FOR NEW HANOVER COUNTY

            A conservative analysis of the components of evacuation time is presented
    below for Wrightsville Beach, for the area south of Snow's Cut, and for Figure
    Eight island. Although other areas in the County along the sounds, creeks, and
    rivers are within hazard areas (estuarine shoreline and 100-year flood plain),
    evacuation for these areas are considered to be adequate because of the short
    length of the evacuation routes, lack of bridges, and low concentrations of
    population served by the routes.

            The analysis utilizes methods and assumptions drawn from work developed
    by the State Office of Coastal Management (McElyea, et al 1983), the Sea Grant
    Program at NCSU (Stone, 1983), and an analysis prepared for Currituck County
    (Collins, 1983). The analysis assumes the following "worst case" scenario:

                                        Page 14

              A severe hurricane, measuring five on the Saffir/Simpson
              Scale, has suddenly shifted direction and is heading
              rapidly toward New Hanover County. The eye of the
              hurricane is expected to reach land within 12 hours.
             The National Weather Service has issued a Hurricane
             Warning and the County's local governments have
              correspondingly issued evacuation orders. Can the
             beaches be evacuated in a safe and timely manner?

           The analysis below is considered conservative because of certain
    assumptions concerning traffic flow and because, in reality, up to 30% of the
    short-term renters and residents would likely leave before the evacuation order
    is issued (Stone, 1983).

        Total Evacuation Time  =  Total Clearance  +  Pre-Landfall Hazard
                                      Time                   Time

                               = 6.61 hours        +  4 hours

                               = 10.61 hours

        The total evacuation time of 11 hours indicates that Wrightsville Beach
    could be safely evacuated if evacuation is ordered concurrent with a typical 12
    hour advance Hurricane Warning. This conservative estimate includes

        Total Clearance Time = Mobilization + Travel + Queuing Delay
                                      Time         Time         Time

                              = 3 hours        +  .25 hours/1 +  3.36 hours/2

                              = 6.61 hours

         /1Travel Time: Under free flow traffic conditions, a car
           should be able to travel from any point on Wrightsville
           Beach to the mainland in a maximum of 15 minutes.

         /2Queuing Delay Time: Queuing delays will result from
           vehicles coming from residential streets onto Highways
           74 and 76 (Waynick Blvd., Lumina Ave., and Causeway Dr.).
           It is assumed that traffic coming off the drawbridge onto
           the mainland will be controlled to prevent traffic back-up
           Calculations are given below:

                                        Page 15

            -Assume that a total of 3150 households and motel room
             groups require evacuation. Each has an average of 1.6
             vehicles per household, for a total of 5040 vehicles.

            -Assume that one half (2200) of the vehicles will
             evacuate from the southern end of the Beach and more than
             one half (2840) simultaneously from the northern end, along two-
             lane roads. The number of vehicles evacuating from the
             northern end include those from the anticipated development
             from Shell Island. For simultaneous evacuation of households
             along those two separate, two-lane stretches of road, therefore,
             maximum queuing delay time would be determined by the larger of
             the two:

                       Queuing     2840  vehicles
                       delay    =  1575 vph capacity
                        time
                                = 1.8 hours

           -Assume that all vehicles (5040) must travel on a four lane
            road to the mainland. This maximum queuing delay time would
            equal:

                       Queuing    5040 vehicles
                       delay    =  3232 vph capacity
                        time
                                = 1.56 hours

          -The Wrightsville Beach drawbridge, according to the N. C. Dept.
            of Transportation, will not be opened during high winds and,
            therefore, would not be a significant delay in traffic.

          -Total maximum        =  1.8 hours  +  1.56 hours
           Queuing delay time
                                = 3.36 hours

    AREA OF COUNTY SOUTH OF SNON'S CUT

        Total Evacuation = Total + Pre-landfall
            Tim     e       Clearance   Hazards
                             Time       Time

                          = 6.22 hours + 4 hours

                          = 10.22 hours

        The total evacuation time of 10.22 hours indicates that this area of the
    County could be safely evacuated if evacuation is ordered concurrent with a
    typical 12 hour advance warning.

        Total Clearance  =  Mobilization  +  Travel  +  Queuing Delay
            Time Tim                         Time           Time

                         =  3 hours       + .5 hours/1  +  2.72 hours/2

                         = 6.22 hours

                                        Page 16

         /lTravel Time: Under free flow traffic conditions, a car should
           be able to travel from any point in the County south of Snow's
           Cut to north of Snow's Cut within 30 minutes.

         /2Queuing delay Time: Queuing delays will result from vehicles
           coming from residential streets onto US 421 (Carolina Beach Road)
           Calculations are given below:

           -Assume that a total of 3635 households and motel room
            groups will require evacuation. Each has an average of
            1.6 vehicles per household, for a total of 5816 vehicles.

           -Assume that one quarter (1454) of the vehicles will
            evacuate from the area south of Carolina Beach north to
            Carolina Beach, using the two-lane section of US 421.

                    Queuing Delay = 1454 vehicles
                       Time           1575 vph capacity

                                  = .92 hours

           -Assume that all vehicles (5816) will evacuate north from
            Carolina Beach to north of Snow's Cut, using the four lane
            section of US 421.

                   Queuing Delay = 5816 vehicles
                      Time           3232 vph capacity

                                     1.80 hours

          -Total maximum queuing   =  .92 hours  +  1.80 hours
           delay time
                                  = 2.72 hours

    FIGURE EIGHT ISLAND

         Total Evacuation  =  Total  +  Pre-Landfall
           Time             Clearance     Hazard
                             Time         Time

                          = 4.12 hours + 4 hours
                          = 8.12 hours

        The total evacuation time of 8.12 hours indicates that Figure Eight Island
    would be safely evacuated if evacuation is ordered concurrent with a 12 hour
    Hurricane Warning.

        Total Clearance :    Mobilization  +  Travel/1  Queuing Delay/2
            Time                 Time          Time         Time

        4.12 hours        =  3 hours       +  .25 hours  +  .87 hours

                                        Page 17

    /1Travel Time: Under free flow traffic conditions, a car should
     be able to travel from either end of Figure Eight Island to the
     mainInd in 15 minutes.

    /2Queuing Delay Time: Queuing delays will result from vehicles
      coming from residences onto Beach Road and then onto Bridge Road.
      Calculations are given below:

     -Assume that a total of 562 households require evacuation. Each
      has an average of 1.6 vehicles per household, for a total of 900
      vehicles.

     -Assume that one half of the vehicles (450) will evacuate
       simultaneously from the northern end. For these two-lane
       stretches of road, therefore, maximum queuing delay time
      would be:

                 Queuing Delay = 450 vehicles
                    Time           1575 vph capacity

                                - .29 hours

      -Assume that all vehicles must travel on the two-lane Bridge
       Road to the mainland. This maximum queuing delay time would be:

                 Queuing Delay = 900 vehicles
                    Time          1575 vph capacity

                                =- .58 hours

     -Total Maximum Queuing      =   .29 hours  +  .58 hours
         Delay Time
                                -   .87 hours

                                   Page 18

          V.   ANALYSIS OF EVACUATION SHELTERS

               According to the American Red Cross, contracts have been made between the
          Red Cross and County schools to use the schools as needed for evacuation
          shelters. Although the Red Cross in Wilmington has certain limited supplies
           (cots, food, clothing) readily available, the Red Cross has established
          agreements with local stores and Red Cross chapters elsewhere to obtain
          additional emergency supplies as needed. The Red Cross also has established
          provisions for emergency medical services and supplies. The Red Cross performs
          these functions as part of their Federal mandate and in accordance with North
          Carolina guidelines from the N. C. Department of Social Services. Principal
          evacuation routes and shelters are shown in Figure 6 attached to the back of the
          report.

     *         ~~The local government is responsible for providing utilities and water.  The
          National Guard is generally relied on for these services. In addition, the local
          Civil Preparedness Office is responsible for coordinating the provision of
    *     ~shelter, supplies, and services.

               According to the Red Cross, the County schools have the capacity to shelter
          17,000 persons. Assuming that only 20-35% of all evacuees (Stone, 1983) would
          utilize the public shelter and that the rest would go to family, friends, motels,
          or outside of the County, this capacity would greatly exceed anticipated use in
          case of a hurricane.

          VI. CONCLUSIONS AND RECOMMENDATIONS

               The results, shown below, of this study indicate that the decision to
          evacuate the beach areas should be made well ahead of the anticipated landfall of
          the hurricane eye:

                                 Clearance Time                 Pre-landfall        Total
          Area of       Mobilization    Travel    Queuing           Hazards        Evacuation
          County           Time          Time    Delay Time         Time             Time
          Wr~ights~vil le
          Beach           3 hrs.         .25 hrs.  3.36 hrs.        4 hrs.         10.61 hrs.
          South of
          snows Cut       3 hrs.         .5  hrs.  2.72 hrs.        4 hrs.         10.22 hrs.
          Figure 8
          Island          3 hrs.         .25 hrs.   .87 hrs.        4 hrs.          8.12 hrs.

               Mobilization time, essentially, is the time required for people to learn of
          the evacuation decision and pack-up. Travel time is the time required to drive
          from the beach. Queuing delay time is the additional time spent in traffic jams
          or other delays. Pre-landfall hazards time is the time when hurricane conditions
          arrive making evacuation unsafe before landfall of the hurricane eye.

               It is important to note that these results are conservative on the safe
          side. The study assumed "worst case" conditions, for instance, in assuming a
          four hour pre-landfall hazards time. In addition, the study assumed that no one
          would leave the beach before evacuation is ordered when, in reality, up to 30% of
          the beach population would probably leave before the order is issued. If this
          "early departure" value was factored in, queuing delay times would be reduced~

                                               Page 19

                The County's decision to evacuate presently is dependent upon the issuance
           of a Hurricane Warning by the National Weather Service. Because the Hurricane
           Warning generally is given at least 12 hours before anticipated landfall of the
           hurricane eye, the calculated total evacuation times indicate the County's
           present decision making framework is adequate for safe and timely evacuation.
           This fortunate situation is primarily due to the presence of four-lane highways
          along major sections of the evacuation routes that would be traveled to reach the
           safety of the mainland. Shelters are also more than adequate.

                It is important to note, howeveri, that total evacuation times for
          Wrightsville Beach and for the area south of Snow's Cut may be approaching the
           critical point where safe evacuation may become excessively difficult. This fact
          emphasizes the need for maintenance of strict control procedures to minimize
          mobilization and queuing delay times, e. g. not permitting sightseers to
           cross over the bridges into the evacuation areas and controlling access at boat
           ramps and marinas, and the need for development of a decision making structure
    *     ~that can quickly order evacuation once the Hurricane Warning is issued, if not
          before.

                in addition, continued growth at Wrightsville Beach and the area south of
          Snow's Cut, particularly Carolina Beach, could eventually result in queuing
          delays that would make evacuation more difficult. The potential of such impacts
           should be considered in the planning of future developments for these areas.

                                               Page 20

                                      REFERENCES

    Carter, T. M., 1981, "Probability of Hurricane/Tropical Storm Conditions: A
    User's Guide for Local Decision Makers," USDOC/NCA-NWS.

    Collins, W. E., 1983, "Carrying Capacity Methodology", Nags Head, NC.

    McElyea, W. D., D. J. Browers, and D. R. Godschalk, 1983 Before the Storm, Center
    for Urban and Regional studies, UNC-Chapel hill.

    Owens, D., 1981, "The Management of Oceanfront Development in North Carolina",
    paper presented at the 7th Annual Conference of The Coastal Society, Oct. 11-14,
    1981, Galveston, Texas.

    Stone, J. R., 1983, "Hurricane Emergency Planning: Estimating Evacuation Times
    for Non-Metropolitan Coastal Communities," Working Paper 83-2, Sea Grant Program,
    NCSU.

    U. S. Corps of Engineers (US COE), 1982, "Feasibility Report and Environmental
    Assessment on Shore and Hurricane Wave Protection", USCOE, Wilmington District.

    ~~~~~~~~~~~~~~~~~~~~~ISLN

                                                        LEGEND
                                                  4f    Figure Eight Island

                                                     *Wrightsville Beach

                                                          Wilmington Beach
                                                              Kure Beach
                                                     *Hoggard High School

                                    WLINATO BEACH * Roland Grise, Jr. High

           Scale In Miles

                               PRINCIP)ALI EVACUATION

                                ROUTES and SHELTERS
                                      NEW HANOVER COUNTY, NC

                                         *~~~~~~~~~~~ Ai

    ~~~~~~~~~~~~~~~~~~~~IN

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